1. Field of the Invention
The present invention relates to display panels.
2. Description of the Related Art
Generally, a liquid crystal display (LCD) when positioned horizontally with its face up includes a lower substrate, an upper substrate facing the lower substrate, and a liquid crystal layer between the upper and lower substrates. The lower substrate includes gate lines and data lines transverse to the gate lines, and also includes pixel electrodes and thin-film transistors (TFT) connected to the gate lines and the data lines to charge the pixel electrodes. The upper substrate includes color filters coordinated with the pixel electrodes and also includes a common electrode facing the pixel electrodes.
In a normally white mode LCD, a pixel is white at a turn-off voltage and black at a turn-on voltage. The liquid crystal has birefringence at the turn-on voltage. When the liquid crystal molecules are substantially normal to the substrates and the LCD is viewed from a direction normal to the substrates, the LCD displays black. However, when viewed from a slanting direction relative to the substrates, the LCD does not necessarily display perfect black because of the birefringence of the liquid crystal. Thus, the LCD has a limited viewing angle. In order to improve the viewing angle, a patterned vertical alignment (PVA) mode has been developed. In the PVA mode LCD, patterns are formed in the common electrode and the pixel electrodes to define multiple domains to appropriately shape the electric field in the liquid crystal. However, in the PVA mode, the pixels in the last horizontal row (i.e. the bottom row when the LCD is vertical) are brighter than the remaining pixels. The image quality is therefore reduced.